Collector
Scale reader
Body-composition measurements from my smart scale, handed to Health.
My scale records more than weight, but only inside its own app. The scale reader brings those measurements somewhere AlanOS can reason over them.
Like the iPhone app, it is a collector: it preserves what was measured and leaves the meaning to the domain.
From the scale to Health
Collect
Apple Watch and iPhone
what HealthKit and location services record
iPhone app
each batch waits on the phone until the home server confirms it has arrived
Smart scale
weight and body composition, stored in the scale's own app
Scale reader
copies each measurement field by field, without changing it
Home server
everything kept exactly as it was recorded, in separate stores
Interpret
Health
reads health data and, through a narrow view, the scale; works out trends against my own normal
Daily
reads location; works out a day's places
- 01
The scale measures
A smart scale estimates weight and body composition each time I step on it, and its own app stores the result.
- 02
The reader copies it
The scale reader collects those measurements into a database I own, field by field, without changing them.
- 03
Checked before trusted
The copied rows were checked against what the scale's own app shows before Health relied on them.
- 04
Health reads it
Health reads the measurements through a narrow view and serves them as part of my body state, next to everything else it knows.
The principles
- Estimates are labelled as estimates
- Body composition from a bathroom scale is a bioimpedance estimate, not a laboratory result. Health says so every time it answers with it.
- A narrow door
- Health can read the measurements and nothing else. The reader owns the data; the domain only has a view of it.
- No interpretation here
- The reader keeps what the scale reported. Trends, ranges and what they mean are worked out in Health.
The measurements feed Health. The iPhone app is the other collector, for the watch, the phone and location.
The scale reader is small, but it carries a rule that runs through all of AlanOS: a number is only useful when you know what kind of number it is.